Please note that all dimensions are given in points, which is a unit equal to 1/72 of an inch. The default chart region is 6” by 4.5” which fits nicely into most published material. This is equivalent to:

chNew 0 0 432 324  © or just 
chNew 432 324

as the default starting location is the lower left corner. To set the charting region to a different shape, or to restrict the chart to a partial area, use this function with (x1,y1,x2,y2) in points from the lower left corner.